Fix ImageDecoder::frameIsCompleteAtIndex - fully received instead of decoded.

third_party/WebKit/Source/platform/image-decoders/bmp/BMPImageReader.h

 /*
  * Copyright (c) 2008, 2009, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 337 matching lines @@
 
     // The coordinate to which we've decoded the image.
     IntPoint m_coord;
 
     // Variables that track whether we've seen pixels with alpha values != 0
     // and == 0, respectively.  See comments in processNonRLEData() on how
     // these are used.
     bool m_seenNonZeroAlphaPixel;
     bool m_seenZeroAlphaPixel;
 
+    // Variables m_seenNonZeroAlphaPixel and m_seenZeroAlphaPixel are tracking
+    // values used for alpha channel.  m_hasPixelsWithAlpha tracks if decoding
+    // saw pixels that are transparent.

[scroggo_chromium, 2016/05/16 20:32:08]

I think this comment is confusing. It describes the variables above (although
better explanations exist elsewhere) and then partially describes
m_hasPixelsWithAlpha.

I think it would be clearer to drop the first sentence and instead say something
like:

// Whether this image is considered to have transparent pixels, after
// taking m_seenNonZeroAlphaPixel and m_seenZeroAlphaPixel into
// consideration.

[aleksandar.stojiljkovic, 2016/05/22 15:41:53]

reverted the code.

+    bool m_hasPixelsWithAlpha;
+
     // BMPs-in-ICOs have a few differences from standalone BMPs, so we need to
     // know if we're in an ICO container.
     bool m_isInICO;
 
     // ICOs store a 1bpp "mask" immediately after the main bitmap image data
     // (and, confusingly, add its height to the biHeight value in the info
     // header, thus doubling it). If |m_isInICO| is true, this variable tracks
     // whether we've begun decoding this mask yet.
     bool m_decodingAndMask;
 };
 
 } // namespace blink
 
 #endif